Viscous Wave Breaking and Ligament Formation in Microfluidic Systems
Viscous Wave Breaking and Ligament Formation in Microfluidic Systems
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DOI：
10.1103/physrevlett.121.044502
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发表时间：
2018-07-27
影响因子：
8.6
通讯作者：
Cubaud, Thomas
中科院分区：
文献类型：
--
作者：
Hu, Xiaoyi;Cubaud, Thomas
微系统中粘性材料的快速分层包括一系列流体动力学不稳定性，这些不稳定性促进具有大粘度差异的流体的混合和乳化过程。我们实验研究的稳定性高粘度分层的可混溶和不混溶流体对在方形微通道和表征的传播动力学的界面波，包括破碎和粘性韧带夹带波峰在中等雷诺数。对于大的粘度对比，平行的流体流采用广泛不同的速度，并提供了一个简单的模型系统，以探讨与经典的无粘稳定性理论的分层微流的屈曲不稳定性的作用。我们揭示了新的粘滞波制度和解开的存在和不存在的界面张力的色散关系。波celebrity的详细检查表明存在的最佳操作条件被动干扰混溶流体流动和连续分散低粘度和高粘度流体在小规模。
Rapid layering of viscous materials in microsystems encompasses a range of hydrodynamic instabilities that facilitate mixing and emulsification processes of fluids having large differences in viscosity. We experimentally study the stability of high-viscosity stratifications made of miscible and immiscible fluid pairs in square microchannels and characterize the propagation dynamics of interfacial waves, including breaking and viscous ligament entrainment from wave crests at moderate Reynolds numbers. For large viscosity contrasts, parallel fluid streams adopt widely different velocities and provide a simple model system to probe the role of inflectional instabilities of stratified microflows in relation with classic inviscid-stability theory. We reveal novel viscous wave regimes and unravel dispersion relationships in the presence and absence of interfacial tension. Detailed examination of wave celerity shows the existence of optimal operation conditions for passively disturbing miscible fluid flows and continuously dispersing low- and high-viscosity fluids at the small scale.